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Master equation,design equations and runaway speed of the Kaplan turbine

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Journal of hydrodynamics 2021年第2期33卷 282-300页

作者： zh.zhang zhAW Zurch University of Applied ScienceZurichSwitzerland

To make the Kaplan turbine technology comparable to both the Pelton and the Francis turbine,the master equation for the Kaplan turbine has been established by analyses similar to that-for the Francis *** analysis begins with the descriptions of free vortex flows at the runner inlet and the swirl flow at the impeller *** considering the Euler equation for specific work and by further evaluating the most significant shock and swirling losses,the first and the second energy equations in the form of hydraulic efficiency were *** master equation is then established by combining both energy *** addition,three design equations and a new design parameter are *** master equation relates the turbine hydromechanics to the geometrical design of both the runner and the guide-vane *** enables the complete hydraulic characteristics of a given Kaplan turbine to be analytically and simply computed.A computation example demonstrates the functionality and applicability of the *** the reconstructed master equation,the runaway speed of the Kaplan turbine and its dependence on the guide-vane setting can be easily and precisely *** bulb turbines with guide vanes directly ahead of the turbine runner in the same tube,all computations are also applicable using another equivalent control parameter.

关键词： Kaplan turbine master equation design equations design parameter runaway speed hydraulic efficiency shock loss swirling loss bulb turbines

Selective De-o-acetylation in TCP-containing Carbohydrate Structures with Magnesium Methoxide

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维普期刊数据库

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Chinese Chemical Letters 2000年第11期11卷 941-944页

作者： Qin, zh Li, h Cai, MS Li, ZJ Beijing Med Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

Magnesium methoxide can be used for TCP-containing substrates to remove acetyl group successfully while leaving the TCP-group virtually intact.

关键词： oCh TCP De

Master equation and runaway speed of the Francis turbine

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Journal of hydrodynamics 2018年第2期30卷 203-217页

作者： zh.zhang Free Researcher Zurich Switzerland

The master equation of the Francis turbine is derived based on the combination of the angular momentum（Euler） and the energy laws. It relates the geometrical design of the impeller and the regulation settings（guide vane angle and rotational speed） to the discharge and the power output. The master equation, thus, enables the complete characteristics of a given Francis turbine to be easily computed. While applying the energy law, both the shock loss at the impeller inlet and the swirling loss at the impeller exit are taken into account. These are main losses which occur at both the partial load and the overloads and, thus, dominantly influence the characteristics of the Francis turbine. They also totally govern the discharge of the water through the impeller when the impeller is found in the standstill. The computations have been performed for the discharge, the hydraulic torque and the hydraulic efficiency. They were also compared with the available measurements on a model turbine. Excellent agreement has been achieved. The computations also enable the runaway speed of the Francis turbine and the related discharge to be determined as a function of the setting angle of the guide vanes.

关键词： Francis turbine master equation runaway speed hydraulic efficiency shock loss swirling loss streamline similarity method

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Journal of hydrodynamics 2018年第1期30卷 140-152页

作者： zh.zhang Free Researcher Zurich Switzerland

An analytical method is presented, which enables the non-uniform velocity and pressure distributions at the impeller inlet of a pump to be accurately computed. The analyses are based on the potential flow theory and the geometrical similarity of the streamline distribution along the leading edge of the impeller blades. The method is thus called streamline similarity method（SSM）. The obtained geometrical form of the flow distribution is then simply described by the geometrical variable G（s） and the first structural constant G_Ⅰ. As clearly demonstrated and also validated by experiments, both the flow velocity and the pressure distributions at the impeller inlet are usually highly non-uniform. This knowledge is indispensible for impeller blade designs to fulfill the shockless inlet flow condition. By introducing the second structural constant G_Ⅱ, the paper also presents the simple and accurate computation of the shock loss, which occurs at the impeller inlet. The introduction of two structural constants contributes immensely to the enhancement of the computational accuracies. As further indicated, all computations presented in this paper can also be well applied to the non-uniform exit flow out of an impeller of the Francis turbine for accurately computing the related mean values.

关键词： Pumps streamline similarity method flow distribution shock loss structural constant

The W-11-4A Platform Comprehensive Strength Monitoring System

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China ocean Engineering 1998年第2期13卷 135-146页

作者： Shen, zh Li, h Xue, YI Chen, JC zh.o, Q Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.

关键词： monitoring techniques comprehensive strength monitoring structural responses waterproof strain transducers underwater instrumentation techniques

SUBSTRUCTURE PRECoNDITIoNERS FoR NoNCoNFoRMIng PLATE ELEMENTS

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Journal of Computational Mathematics 1998年第4期16卷 289-304页

作者： Shi, ZC Xie, zh Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

In this paper, we consider the problem of solving finite element equations of biharmonic Dirichlet problems. We divide the given domain into non-overlapping subdomains, construct a preconditioner for Morley element by substructuring on the basis of a function decomposition for discrete biharmonic functions. The function decomposition is introduced by partitioning these finite element functions into the low and high frequency components through the intergrid transfer operators between coarse mesh and fine mesh, and the conforming interpolation operators. The method leads to a preconditioned system with the condition number bounded by C(1 + log(2) h/h) in the case with interior cross points, and by C in the case without interior cross points, where h is the subdomain size and h is the mesh size. These techniques are applicable to other nonconforming elements and are well suited to a parallel computation.

关键词： substructure preconditioner biharmonic equation nonconforming plate element

Sensitive analysis of amino acids in injection liquor by reversed-phase hPLC

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Chinese Journal of Chemistry 1995年第2期13卷 163-168页

作者： ShAng, zh YU, YN GUo, W JIAng, h zhoU, LM ChINESE ACAD SCI DALIAN INST CHEM PHYSDALIAN 116012PEOPLES R CHINA

A convenient derivatization method of amino acids with 1-fluoro-2,4-dinitrobezene as reaction reagent and a separation system were described. The derivative amino acids were separated on a specific chemically bonded phase column with a simple linear gradient elution consisting of aqueous buffer and methanol. The eluate was detected by common ultraviolet absorption detector at 360 nm. The detection limits of amino acids were as low as 10 picomole. This method has been successfully applied to assay amino acid injection liquor used in hospital. It has good reproducibility and precision. The procedures avoid the requirements of particular derivative equipment and analyzer employed in conventional amino acid analysis.

关键词： AMINo ACIDS PRECoLUMN DERIVATIZATIoN REVERSED PhASE SEPARATIoN UV ABSoRPTIoN DETERMINATIoN

MULTIGRID METhoDS FoR MoRLEY ELEMENT oN NoNNESTED MEShES

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Journal of Computational Mathematics 1998年第5期16卷 385-394页

作者： Shi, ZC Xie, zh Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

In this paper, we consider some multigrid algorithms for the biharmonic problem discretized by Morley element on nonnested meshes. Through taking the averages of the nodal variables we construct an intergrid transfer operator that satisfies a certain stable approximation property. The so-called regularity-approximation assumption is then established. optimal convergence properties of the W-cycle and a uniform condition number estimate for the variable V-cycle preconditioner are presented. This technique is applicable to other nonconforming plate elements.

关键词： multigrid method Morley element nonnested meshes

Laser and Fluorescence Properties of organic Dye DCM Doped Sol-Gel-Derived Solid-State Materials

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Journal of Materials Science & Technology 1999年第6期15卷 563-566页

作者： zhang, QY Jiang, zh Tongji Univ Pohl Inst Solid State Phys Shanghai 200092 Peoples R China Chinese Acad Sci Shanghai Inst Opt & Fine Mech Shanghai 201800 Peoples R China

Two kinds of new ormosil xerogels derived from GPTMS (3-glycidyl propyl trimethoxisilane) and TEoS (tetraethoxysilane) or GPTMS and Ti(oBu)4 (tetrabutoxytitanate) were synthesized viathe sol-gel method as dye laser host. Their optical properties, microstructure characteristics and sudece laser damage thresholds have been reported. The effects of dye matrix combination on the fluorescence emission, slope efficiency, photostability and tunable bandwidth were *** oscillation was easily achieved near 620 nm with a slope efficiency of 29% from DCM dopedSio2-ormosil pumped by a frequency-doubled radiation from a Q-switched Nd:YAG laser. The laser wavelength was tunable over 59 nm, and the laser output energy had only a 10% reduction after 2.5× 104 pulses at a pump repetition rate of 1hz and a pump intensity of 1

关键词： GPTMS DCM Etoh